| MKVMERGE(1) | User Commands | MKVMERGE(1) |
mkvmerge - Merge multimedia streams into a Matroska file
mkvmerge [global options] {-o out} [options1] {file1} [[options2] {file2}] [@options-file.json]
This program takes the input from several media files and joins their streams (all of them or just a selection) into a Matroska file; see the Matroska website[1].
The order of command line options is important. Please read the section "Option order" if you're new to the program.
-v, --verbose
-q, --quiet
-o, --output file-name
-w, --webm
For chapters and tags only a subset of elements are allowed. mkvmerge(1) will automatically remove all elements not allowed by the specification.
--title title
--default-language language-code
The default language code is 'und' for 'undefined'.
--segmentinfo filename.xml
See the section about segment info XML files below for details.
--segment-uid SID1,SID2,...
If SID starts with = then its rest is interpreted as the name of a Matroska file whose segment UID is read and used.
Each file created contains one segment, and each segment has one segment UID. If more segment UIDs are specified than segments are created then the surplus UIDs are ignored. If fewer UIDs are specified than segments are created then random UIDs will be created for them.
--chapter-language language-code
This option can be used both for simple chapter files and for source files that contain chapters but no information about the chapters' language, e.g. MP4 and OGM files.
The language set with this option is also used when chapters are generated with the --generate-chapters option.
--chapter-charset character-set
This switch does also apply to chapters that are copied from certain container types, e.g. Ogg/OGM and MP4 files. See the section about chapters below for details.
--chapter-sync d[,o[/p]]
o/p: adjust the timestamps by o/p to fix linear drifts. p defaults to 1 if omitted. Both o and p can be floating point numbers.
Defaults: no manual sync correction (which is the same as d = 0 and o/p = 1.0).
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
--generate-chapters mode
Example: --generate-chapters interval:45s
The names for the new chapters are controlled by the option --generate-chapters-name-template. The language is set with --chapter-language which must occur before --generate-chapters.
--generate-chapters-name-template template
There are several variables that can be used in the template that are replaced by their actual values when a chapter is generated. The string '<NUM>' will be replaced by the chapter number. The string '<START>' will be replaced by the chapter's start timestamp.
The strings '<FILE_NAME>' and '<FILE_NAME_WITH_EXT>' are only filled when generating chapters for appended files. They will be replaced by the appended file's name wihtout respectively with its extension. Note that only the file's base name and extension are inserted, not its directory or drive components.
You can specify a minimum number of places for the chapter number with '<NUM:places>', e.g. '<NUM:3>'. The resulting number will be padded with leading zeroes if the number of places is less than specified.
You can control the format used by the start timestamp with <START:format>. The format defaults to '%H:%M:%S' if none is given. Valid format codes are:
--cue-chapter-name-format format
If this option is not given then mkvmerge(1) defaults to the format '%p - %t' (the performer, followed by a space, a dash, another space and the title).
If the format is given then everything except the following meta characters is copied as-is, and the meta characters are replaced like this:
--chapters file-name
--global-tags file-name
--track-order FID1:TID1,FID2:TID2,...
--cluster-length spec
If no unit is used then mkvmerge(1) will put at most n data blocks into each cluster. The maximum number of blocks is 65535.
If the number d is postfixed with 'ms' then mkvmerge(1) puts at most d milliseconds of data into each cluster. The minimum for d is '100ms', and the maximum is '32000ms'.
mkvmerge(1) defaults to putting at most 65535 data blocks and 5000ms of data into a cluster.
Programs trying to find a certain frame can only seek directly to a cluster and have to read the whole cluster afterwards. Therefore creating larger clusters may lead to imprecise or slow seeking.
--no-cues
--clusters-in-meta-seek
--disable-lacing
--enable-durations
--disable-track-statistics-tags
Enabling this option prevents mkvmerge(1) from writing those tags and from touching any existing tags with same names.
--timestamp-scale factor
Normally mkvmerge(1) will use a value of 1000000 which means that timestamps and durations will have a precision of 1ms. For files that will not contain a video track but at least one audio track mkvmerge(1) will automatically chose a timestamp scale factor so that all timestamps and durations have a precision of one audio sample. This causes bigger overhead but allows precise seeking and extraction.
If the special value -1 is used then mkvmerge(1) will use sample precision even if a video track is present.
--split specification
At the moment mkvmerge(1) supports four different modes.
Syntax: --split [size:]d[k|m|g]
Examples: --split size:700m or --split 150000000
The parameter d may end with 'k', 'm' or 'g' to indicate that the size is in KB, MB or GB respectively. Otherwise a size in bytes is assumed. After the current output file has reached this size limit a new one will be started.
The 'size:' prefix may be omitted for compatibility reasons.
Syntax: --split [duration:]HH:MM:SS.nnnnnnnnn|ds
Examples: --split duration:00:60:00.000 or --split 3600s
The parameter must either have the form HH:MM:SS.nnnnnnnnn for specifying the duration in up to nano-second precision or be a number d followed by the letter 's' for the duration in seconds. HH is the number of hours, MM the number of minutes, SS the number of seconds and nnnnnnnnn the number of nanoseconds. Both the number of hours and the number of nanoseconds can be omitted. There can be up to nine digits after the decimal point. After the duration of the contents in the current output has reached this limit a new output file will be started.
The 'duration:' prefix may be omitted for compatibility reasons.
Syntax: --split timestamps:A[,B[,C...]]
Example: --split timestamps:00:45:00.000,01:20:00.250,6300s
The parameters A, B, C etc must all have the same format as the ones used for the duration (see above). The list of timestamps is separated by commas. After the input stream has reached the current split point's timestamp a new file is created. Then the next split point given in this list is used.
The 'timestamps:' prefix must not be omitted.
Syntax: --split parts:start1-end1[,[+]start2-end2[,[+]start3-end3...]]
Examples:
The parts mode tells mkvmerge(1) to keep certain ranges of timestamps while discarding others. The ranges to keep have to be listed after the parts: keyword and be separated by commas. A range itself consists of a start and an end timestamp in the same format the other variations of --split accept (e.g. both 00:01:20 and 80s refer to the same timestamp).
If a start timestamp is left out then it defaults to the previous range's end timestamp. If there was no previous range then it defaults to the start of the file (see example 3).
If an end timestamp is left out then it defaults to the end of the source files which basically tells mkvmerge(1) to keep the rest (see example 3).
Normally each range will be written to a new file. This can be changed so that consecutive ranges are written to the same file. For that the user has to prefix the start timestamp with a +. This tells mkvmerge(1) not to create a new file and instead append the range to the same file the previous range was written to. Timestamps will be adjusted so that there will be no gap in the output file even if there was a gap in the two ranges in the input file.
In example 1 mkvmerge(1) will create two files. The first will contain the content starting from 00:01:20 until 00:02:45. The second file will contain the content starting from 00:05:50 until 00:10:30.
In example 2 mkvmerge(1) will create only one file. This file will contain both the content starting from 00:01:20 until 00:02:45 and the content starting from 00:05:50 until 00:10:30.
In example 3 mkvmerge(1) will create two files. The first will contain the content from the start of the source files until 00:02:45. The second file will contain the content starting from 00:05:50 until the end of the source files.
Syntax: --split parts-frames:start1-end1[,[+]start2-end2[,[+]start3-end3...]]
Examples:
The parts-frames mode tells mkvmerge(1) to keep certain ranges of frame/field numbers while discarding others. The ranges to keep have to be listed after the parts-frames: keyword and be separated by commas. A range itself consists of a start and an end frame/field number. Numbering starts at 1.
If a start number is left out then it defaults to the previous range's end number. If there was no previous range then it defaults to the start of the file (see example 3).
If an end number is left out then it defaults to the end of the source files which basically tells mkvmerge(1) to keep the rest (see example 3).
Normally each range will be written to a new file. This can be changed so that consecutive ranges are written to the same file. For that the user has to prefix the start number with a +. This tells mkvmerge(1) not to create a new file and instead append the range to the same file the previous range was written to. Timestamps will be adjusted so that there will be no gap in the output file even if there was a gap in the two ranges in the input file.
In example 2 mkvmerge(1) will create only one file. This file will contain both the content starting from 733 until 912 and the content starting from 1592 until 2730.
In example 3 mkvmerge(1) will create two files. The first will contain the content from the start of the source files until 430. The second file will contain the content starting from 2512 until the end of the source files.
This mode considers only the first video track that is output. If no video track is output no splitting will occur.
Syntax: --split frames:A[,B[,C...]]
Example: --split frames:120,237,891
The parameters A, B, C etc must all be positive integers. Numbering starts at 1. The list of frame/field numbers is separated by commas. After the input stream has reached the current split point's frame/field number a new file is created. Then the next split point given in this list is used.
The 'frames:' prefix must not be omitted.
This mode considers only the first video track that is output. If no video track is output no splitting will occur.
Syntax: --split chapters:all or --split chapters:A[,B[,C...]]
Example: --split chapters:5,8
The parameters A, B, C etc must all be positive integers. Numbering starts at 1. The list of chapter numbers is separated by commas. Splitting will occur right before the first key frame whose timestamp is equal to or bigger than the start timestamp for the chapters whose numbers are listed. A chapter starting at 0s is never considered for splitting and discarded silently.
The keyword all can be used instead of listing all chapter numbers manually.
The 'chapters:' prefix must not be omitted.
For this splitting mode the output filename is treated differently than for the normal operation. It may contain a printf like expression '%d' including an optional field width, e.g. '%02d'. If it does then the current file number will be formatted appropriately and inserted at that point in the filename. If there is no such pattern then a pattern of '-%03d' is assumed right before the file's extension: '-o output.mkv' would result in 'output-001.mkv' and so on. If there's no extension then '-%03d' will be appended to the name.
--link
--link-to-previous segment-UID
If SID starts with = then its rest is interpreted as the name of a Matroska file whose segment UID is read and used.
--link-to-next segment-UID
If SID starts with = then its rest is interpreted as the name of a Matroska file whose segment UID is read and used.
--append-mode mode
When mkvmerge appends a track (called 'track2_1' from now on) from a second file (called 'file2') to a track (called 'track1_1') from the first file (called 'file1') then it has to offset all timestamps for 'track2_1' by an amount. For 'file' mode this amount is the highest timestamp encountered in 'file1' even if that timestamp was from a different track than 'track1_1'. In track mode the offset is the highest timestamp of 'track1_1'.
Unfortunately mkvmerge cannot detect which mode to use reliably. Therefore it defaults to 'file' mode. 'file' mode usually works better for files that have been created independently of each other; e.g. when appending AVI or MP4 files. 'track' mode may work better for sources that are essentially just parts of one big file, e.g. for VOB and EVO files.
Subtitle tracks are always treated as if 'file' mode were active even if 'track' mode actually is.
--append-to SFID1:STID1:DFID1:DTID1[,...]
If this option has been omitted then a standard mapping is used. This standard mapping appends each track from the current file to a track from the previous file with the same track ID. This allows for easy appending if a movie has been split into two parts and both file have the same number of tracks and track IDs with the command mkvmerge -o output.mkv part1.mkv +part2.mkv.
+
$ mkvmerge -o full.mkv file1.mkv + file2.mkv $ mkvmerge -o full.mkv file1.mkv +file2.mkv
[ file1 file2 ]
This is an alternative syntax to using '+' between the file names. Therefore the following two commands are equivalent:
$ mkvmerge -o full.mkv file1.mkv + file2.mkv $ mkvmerge -o full.mkv '[' file1.mkv file2.mkv ']'
=
The '=' can also be put in front of the next file name. Therefore the following two commands are equivalent:
$ mkvmerge -o full.mkv = file1.mkv $ mkvmerge -o full.mkv =file1.mkv
( file1 file2 )
This can be used for e.g. VOB files coming from a DVD or MPEG transport streams. It cannot be used if each file contains its own set of headers which is usually the case with stand-alone files like AVI or MP4.
Putting a file name into parenthesis also prevents mkvmerge(1) from looking for additional files with the same base name as described in option =. Therefore these two command lines are equivalent:
$ mkvmerge -o out.mkv = file.mkv
$ mkvmerge -o out.mkv '(' file.mkv ')'
Several things should be noted:
--attachment-description description
--attachment-mime-type MIME type
--attachment-name name
--attach-file file-name, --attach-file-once file-name
mkvextract(1) can be used to extract attached files from a Matroska file.
-a, --audio-tracks [!]n,m,...
Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks.
Default: copy all tracks of this kind.
If the IDs are prefixed with ! then the meaning is reversed: copy all tracks of this kind but the ones listed after the !.
-d, --video-tracks [!]n,m,...
Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks.
If the IDs are prefixed with ! then the meaning is reversed: copy all tracks of this kind but the ones listed after the !.
-s, --subtitle-tracks [!]n,m,...
Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks.
If the IDs are prefixed with ! then the meaning is reversed: copy all tracks of this kind but the ones listed after the !.
-b, --button-tracks [!]n,m,...
Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks.
If the IDs are prefixed with ! then the meaning is reversed: copy all tracks of this kind but the ones listed after the !.
--track-tags [!]n,m,...
If the IDs are prefixed with ! then the meaning is reversed: copy everything but the IDs listed after the !.
-m, --attachments [!]n[:all|first],m[:all|first],...
The default is to copy all attachments to all output files.
If the IDs are prefixed with ! then the meaning is reversed: copy everything but the IDs listed after the !.
-A, --no-audio
-D, --no-video
-S, --no-subtitles
-B, --no-buttons
-T, --no-track-tags
--no-chapters
-M, --no-attachments
--no-global-tags
--chapter-charset character-set
--chapter-language language-code
-y, --sync TID:d[,o[/p]]
o/p: adjust the timestamps by o/p to fix linear drifts. p defaults to 1 if omitted. Both o and p can be floating point numbers.
Defaults: no manual sync correction (which is the same as d = 0 and o/p = 1.0).
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
--cues TID:none|iframes|all
The default is 'iframes' for video and subtitle tracks and 'none' for audio tracks. See also option --no-cues which inhibits the creation of cue entries regardless of the --cues options used.
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
--default-track TID[:bool]
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
--forced-track TID[:bool]
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
--blockadd TID:level
--track-name TID:name
--language TID:language
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
-t, --tags TID:file-name
--aac-is-sbr TID[:0|1]
If the source file is a Matroska file then the CodecID should be enough to detect SBR AAC. However, if the CodecID is wrong then this switch can be used to correct that.
If mkvmerge wrongfully detects that an AAC file is SBR then you can add ':0' to the track ID.
--reduce-to-core TID
Currently only DTS tracks are affected by this option. TrueHD tracks that contain an embedded AC-3 core are instead presented as two separate tracks for which the user can select which track to copy. For DTS such a scheme would not work as the HD extensions cannot be decoded by themselves – unlike the TrueHD data.
--remove-dialog-normalization-gain TID
Currently only AC-3, DTS and TrueHD tracks are affected by this option.
--timestamps TID:file-name
--default-duration TID:x
If the default duration is not forced then mkvmerge will try to derive the track's default duration from the container and/or the encoded bitstream for certain track types, e.g. AVC/h.264 or MPEG-2.
This option can also be used to change the FPS of video tracks without having to use an external timestamp file.
--fix-bitstream-timing-information TID[:0|1]
--nalu-size-length TID:n
--compression TID:n
The compression method 'mpeg4_p2'/'mpeg4p2' is a special compression method called 'header removal' that is only available for MPEG4 part 2 video tracks.
The default for some subtitle types is 'zlib' compression. This compression method is also the one that most if not all playback applications support. Support for other compression methods other than 'none' is not assured.
-f, --fourcc TID:FourCC
--display-dimensions TID:widthxheight
Another way to specify the values is to use the --aspect-ratio or the --aspect-ratio-factor option (see below). These options are mutually exclusive.
--aspect-ratio TID:ratio|width/height
Another way to specify the values is to use the --aspect-ratio-factor or --display-dimensions options (see above and below). These options are mutually exclusive.
--aspect-ratio-factor TID:factor|n/d
Another way to specify the values is to use the --aspect-ratio or --display-dimensions options (see above). These options are mutually exclusive.
--cropping TID:left,top,right,bottom
--colour-matrix TID:n
Valid values and their meaning are:
0: GBR, 1: BT709, 2: unspecified, 3: reserved, 4: FCC, 5: BT470BG, 6: SMPTE 170M, 7: SMPTE 240M, 8: YCOCG, 9: BT2020 non-constant luminance, 10: BT2020 constant luminance
--colour-bits-per-channel TID:n
--chroma-subsample TID:hori,vert
Example: For video with 4:2:0 chroma subsampling, the parameter should be set to TID:1,1.
--cb-subsample TID:hori,vert
Example: For video with 4:2:1 chroma subsampling, the parameter --chroma-subsample should be set to TID:1,0 and Cb-subsample should be set to TID:1,0.
--chroma-siting TID:hori,vert
--colour-range TID:n
--colour-transfer-characteristics TID:n
Valid values and their meaning are:
0: reserved, 1: ITU-R BT.709, 2: unspecified, 3: reserved, 4: gamma 2.2 curve, 5: gamma 2.8 curve, 6: SMPTE 170M, 7: SMPTE 240M, 8: linear, 9: log, 10: log sqrt, 11: IEC 61966-2-4, 12: ITU-R BT.1361 extended colour gamut, 13: IEC 61966-2-1, 14: ITU-R BT.2020 10 bit, 15: ITU-R BT.2020 12 bit, 16: SMPTE ST 2084, 17: SMPTE ST 428-1; 18: ARIB STD-B67 (HLG)
--colour-primaries TID:n
Valid values and their meaning are:
0: reserved, 1: ITU-R BT.709, 2: unspecified, 3: reserved, 4: ITU-R BT.470M, 5: ITU-R BT.470BG, 6: SMPTE 170M, 7: SMPTE 240M, 8: FILM, 9: ITU-R BT.2020, 10: SMPTE ST 428-1, 22: JEDEC P22 phosphors
--max-content-light TID:n
--max-frame-light TID:n
--chromaticity-coordinates TID:red-x,red-y,green-x,green-y,blue-x,blue-y
--white-colour-coordinates TID:x,y
--max-luminance TID:float
--min-luminance TID:float
--projection-type TID:method
--projection-private TID:data
--projection-pose-yaw TID:float
--projection-pose-pitch TID:float
--projection-pose-roll TID:float
--field-order TID:n
0: progressive; 1: interlaced with top field displayed first and top field stored first; 2: undetermined field order; 6: interlaced with bottom field displayed first and bottom field stored first; 9: interlaced with bottom field displayed first and top field stored first; 14: interlaced with top field displayed first and bottom field stored first
--stereo-mode TID:n|keyword
'mono', 'side_by_side_left_first', 'top_bottom_right_first', 'top_bottom_left_first', 'checkerboard_right_first', 'checkerboard_left_first', 'row_interleaved_right_first', 'row_interleaved_left_first', 'column_interleaved_right_first', 'column_interleaved_left_first', 'anaglyph_cyan_red', 'side_by_side_right_first', 'anaglyph_green_magenta', 'both_eyes_laced_left_first', 'both_eyes_laced_right_first'.
--sub-charset TID:character-set
This option can be used multiple times for an input file applying to several tracks by selecting different track IDs each time.
-i, --identify file-name
The output format used for the result can be changed with the option --identification-format.
-J file-name
-F, --identification-format format
This format is not meant to be parsed. The output will be translated into the language mkvmerge(1) uses (see also --ui-language).
mkvmerge-identification-output-schema-v11.json[3]
All versions of the JSON schema are available both online and in the released source code archives.
--probe-range-percentage percentage
If tracks are known to be present but not found then the percentage to probe can be changed with this option. The minimum of 10 MB is built-in and cannot be changed.
-l, --list-types
--list-languages
--priority priority
Selecting 'lowest' also causes mkvmerge(1) to select idle I/O priority in addition to the lowest possible process priority.
--command-line-charset character-set
--output-charset character-set
-r, --redirect-output file-name
--flush-on-close
--ui-language code
--abort-on-warnings
--debug topic
--engage feature
--gui-mode
@options-file.json
--capabilities
-h, --help
-V, --version
For each file the user can select which tracks mkvmerge(1) should take. They are all put into the file specified with -o. A list of known (and supported) source formats can be obtained with the -l option.
The order of command line options is important. Please read the section "Option order" if you're new to the program.
The order in which options are entered is important for some options. Options fall into two categories:
The options are processed from left to right. If an option appears multiple times within the same scope then the last occurence will be used. Therefore the title will be set to "Something else" in the following example:
$ mkvmerge -o output.mkv --title 'This and that' input.avi --title 'Something else'
The following example shows that using the --language option twice is OK because they're used in different scopes. Even though they apply to the same track ID they apply to different input files and therefore have different scopes:
$ mkvmerge -o output.mkv --language 0:fre français.ogg --language 0:deu deutsch.ogg
Let's assume you have a file called MyMovie.avi and the audio track in a separate file, e.g. 'MyMovie.wav'. First you want to encode the audio to OggVorbis:
$ oggenc -q4 -oMyMovie.ogg MyMovie.wav
After a couple of minutes you can join video and audio:
$ mkvmerge -o MyMovie-with-sound.mkv MyMovie.avi MyMovie.ogg
If your AVI already contains an audio track then it will be copied as well (if mkvmerge(1) supports the audio format). To avoid that simply do
$ mkvmerge -o MyMovie-with-sound.mkv -A MyMovie.avi MyMovie.ogg
After some minutes of consideration you rip another audio track, e.g. the director's comments or another language to 'MyMovie-add-audio.wav'. Encode it again and join it up with the other file:
$ oggenc -q4 -oMyMovie-add-audio.ogg MyMovie-add-audio.wav $ mkvmerge -o MM-complete.mkv MyMovie-with-sound.mkv MyMovie-add-audio.ogg
The same result can be achieved with
$ mkvmerge -o MM-complete.mkv -A MyMovie.avi MyMovie.ogg MyMovie-add-audio.ogg
Now fire up mplayer and enjoy. If you have multiple audio tracks (or even video tracks) then you can tell mplayer which track to play with the '-vid' and '-aid' options. These are 0-based and do not distinguish between video and audio.
If you need an audio track synchronized you can do that easily. First find out which track ID the Vorbis track has with
$ mkvmerge --identify outofsync.ogg
Now you can use that ID in the following command line:
$ mkvmerge -o goodsync.mkv -A source.avi -y 12345:200 outofsync.ogg
This would add 200ms of silence at the beginning of the audio track with the ID 12345 taken from 'outofsync.ogg'.
Some movies start synced correctly but slowly drift out of sync. For these kind of movies you can specify a delay factor that is applied to all timestamps -- no data is added or removed. So if you make that factor too big or too small you'll get bad results. An example is that an episode I transcoded was 0.2 seconds out of sync at the end of the movie which was 77340 frames long. At 29.97fps 0.2 seconds correspond to approx. 6 frames. So I did
$ mkvmerge -o goodsync.mkv -y 23456:0,77346/77340 outofsync.mkv
The result was fine.
The sync options can also be used for subtitles in the same manner.
For text subtitles you can either use some Windows software (like SubRipper) or the subrip package found in transcode(1)'s sources in the 'contrib/subrip' directory. The general process is:
$ tccat -i /path/to/copied/dvd/ -T 1 -L | tcextract -x ps1 -t vob -a 0x20 | subtitle2pgm -o mymovie
$ pgm2txt mymovie
$ ispell -d american *txt
$ srttool -s -w -i mymovie.srtx -o mymovie.srt
The resulting file can be used as another input file for mkvmerge(1):
$ mkvmerge -o mymovie.mkv mymovie.avi mymovie.srt
If you want to specify the language for a given track then this is easily done. First find out the ISO639-2 code for your language. mkvmerge(1) can list all of those codes for you:
$ mkvmerge --list-languages
Search the list for the languages you need. Let's assume you have put two audio tracks into a Matroska file and want to set their language codes and that their track IDs are 2 and 3. This can be done with
$ mkvmerge -o with-lang-codes.mkv --language 2:ger --language 3:dut without-lang-codes.mkv
As you can see you can use the --language switch multiple times.
Maybe you'd also like to have the player use the Dutch language as the default language. You also have extra subtitles, e.g. in English and French, and want to have the player display the French ones by default. This can be done with
$ mkvmerge -o with-lang-codes.mkv --language 2:ger --language 3:dut --default-track 3 without-lang-codes.mkv --language 0:eng english.srt --default-track 0 --language 0:fre french.srt
If you do not see the language or default track flags that you've specified in mkvinfo(1)'s output then please read the section about default values.
Turn off the compression for an input file.
$ mkvmerge -o no-compression.mkv --compression -1:none MyMovie.avi --compression -1:none mymovie.srt
Some of the options for mkvmerge(1) need a track ID to specify which track they should be applied to. Those track IDs are printed by the readers when demuxing the current input file, or if mkvmerge(1) is called with the --identify option. An example for such output:
$ mkvmerge -i v.mkv File 'v.mkv': container: Matroska Track ID 0: video (V_MS/VFW/FOURCC, DIV3) Track ID 1: audio (A_MPEG/L3)
Do not confuse the track IDs that are assigned to the tracks that are placed in the output MKV file with the track IDs of the input files. Only the input file track IDs are used for options needing these values.
Also note that each input file has its own set of track IDs. Therefore the track IDs for file 'file1.ext' as reported by 'mkvmerge --identify' do not change no matter how many other input files are there or in which position 'file1.ext' is used.
Track IDs are assigned like this:
The options that use the track IDs are the ones whose description contains 'TID'. The following options use track IDs as well: --audio-tracks, --video-tracks, --subtitle-tracks, --button-tracks and --track-tags.
There are several IDs that have special meaning and do not occur in the identification output.
The special track ID '-1' is a wild card and applies the given switch to all tracks that are read from an input file.
The special track ID '-2' refers to the chapters in a source file. Currently only the --sync option uses this special ID. As an alternative to --sync -2:... the option --chapter-sync ... can be used.
All text in a Matroska file is encoded in UTF-8. This means that mkvmerge(1) has to convert every text file it reads as well as every text given on the command line from one character set into UTF-8. In return this also means that mkvmerge(1)'s output has to be converted back to that character set from UTF-8, e.g. if a non-English translation is used with --ui-language or for text originating from a Matroska file.
mkvmerge(1) does this conversion automatically based on the presence of a byte order marker (short: BOM) or the system's current locale. How the character set is inferred from the locale depends on the operating system that mkvmerge(1) is run on.
Text files that start with a BOM are already encoded in one representation of UTF. mkvmerge(1) supports the following five modes: UTF-8, UTF-16 Little and Big Endian, UTF-32 Little and Big Endian. Text files with a BOM are automatically converted to UTF-8. Any of the parameters that would otherwise set the character set for such a file (e.g. --sub-charset) is silently ignored.
On Unix-like systems mkvmerge(1) uses the setlocale(3) system call which in turn uses the environment variables LANG, LC_ALL and LC_CYPE. The resulting character set is often one of UTF-8 or the ISO-8859-* family and is used for all text file operations and for encoding strings on the command line and for output to the console.
On Windows the default character set used for converting text files is determined by a call to the GetACP() system call.
Reading the command line is done with the GetCommandLineW() function which already returns a Unicode string. Therefore the option --command-line-charset is ignored on Windows.
Output to the console consists of three scenarios:
If the output is redirected with cmd.exe itself, e.g. with mkvinfo file.mkv > info.txt, then the charset is always UTF-8 and cannot be changed.
Otherwise (when writing directly to the console) the Windows function WriteConsoleW() is used and the option --output-charset is ignored. The console should be able to output all Unicode characters for which the corresponding language support is installed (e.g. Chinese characters might not be displayed on English Windows versions).
The following options exist that allow specifying the character sets:
An option file is a file mkvmerge(1) can read additional command line arguments from. This can be used in order to circumvent certain limitations of the shell or the operating system when executing external programs like a limited command line length.
An option file contains JSON-formatted data. Its content must be a valid JSON array consisting solely of JSON strings. The file's encoding must be UTF-8. The file should not start with a byte order marker (BOM), but if one exists, it will be skipped.
The rules for escaping special characters inside JSON are the ones in the official JSON specification, RFC 7159[4].
The command line 'mkvmerge -o "my file.mkv" -A "a movie.avi" sound.ogg' could be converted into the following JSON option file called e.g. 'options.json':
[
"-o",
"c:\\Matroska\\my file.mkv",
"--title",
"#65",
"-A",
"a movie.avi",
"sound.ogg" ]
There are several text and bitmap subtitle formats that can be embedded into Matroska. Text subtitles must be recoded to UTF-8 so that they can be displayed correctly by a player (see the section about text files and character sets for an explanation how mkvmerge(1) converts between character sets). Kate subtitles are already encoded in UTF-8 and do not have to be re-encoded.
The following subtitle formats are supported at the moment:
Matroska supports file linking which simply says that a specific file is the predecessor or successor of the current file. To be precise, it's not really the files that are linked but the Matroska segments. As most files will probably only contain one Matroska segment the following explanations use the term 'file linking' although 'segment linking' would be more appropriate.
Each segment is identified by a unique 128 bit wide segment UID. This UID is automatically generated by mkvmerge(1). The linking is done primarily via putting the segment UIDs (short: SID) of the previous/next file into the segment header information. mkvinfo(1) prints these SIDs if it finds them.
If a file is split into several smaller ones and linking is used then the timestamps will not start at 0 again but will continue where the last file has left off. This way the absolute time is kept even if the previous files are not available (e.g. when streaming). If no linking is used then the timestamps should start at 0 for each file. By default mkvmerge(1) does not use file linking. If you want that you can turn it on with the --link option. This option is only useful if splitting is activated as well.
Regardless of whether splitting is active or not the user can tell mkvmerge(1) to link the produced files to specific SIDs. This is achieved with the options --link-to-previous and --link-to-next. These options accept a segment SID in the format that mkvinfo(1) outputs: 16 hexadecimal numbers between 0x00 and 0xff prefixed with '0x' each, e.g. '0x41 0xda 0x73 0x66 0xd9 0xcf 0xb2 0x1e 0xae 0x78 0xeb 0xb4 0x5e 0xca 0xb3 0x93'. Alternatively a shorter form can be used: 16 hexadecimal numbers between 0x00 and 0xff without the '0x' prefixes and without the spaces, e.g. '41da7366d9cfb21eae78ebb45ecab393'.
If splitting is used then the first file is linked to the SID given with --link-to-previous and the last file is linked to the SID given with --link-to-next. If splitting is not used then the one output file will be linked to both of the two SIDs.
The Matroska specification states that some elements have a default value. Usually an element is not written to the file if its value is equal to its default value in order to save space. The elements that the user might miss in mkvinfo(1)'s output are the language and the default track flag elements. The default value for the language is English ('eng'), and the default value for the default track flag is true. Therefore if you used --language 0:eng for a track then it will not show up in mkvinfo(1)'s output.
Maybe you also want to keep some photos along with your Matroska file, or you're using SSA subtitles and need a special TrueType font that's really rare. In these cases you can attach those files to the Matroska file. They will not be just appended to the file but embedded in it. A player can then show those files (the 'photos' case) or use them to render the subtitles (the 'TrueType fonts' case).
Here's an example how to attach a photo and a TrueType font to the output file:
$ mkvmerge -o output.mkv -A video.avi sound.ogg \
--attachment-description "Me and the band behind the stage in a small get-together" \
--attachment-mime-type image/jpeg \
--attach-file me_and_the_band.jpg \
--attachment-description "The real rare and unbelievably good looking font" \
--attachment-mime-type application/octet-stream \
--attach-file really_cool_font.ttf
If a Matroska containing attachments file is used as an input file then mkvmerge(1) will copy the attachments into the new file. The selection which attachments are copied and which are not can be changed with the options --attachments and --no-attachments.
The Matroska chapter system is more powerful than the old known system used by OGM files. The full specifications can be found at the Matroska website[1].
mkvmerge(1) supports two kinds of chapter files as its input. The first format, called 'simple chapter format', is the same format that the OGM tools expect. The second format is a XML based chapter format which supports all of Matroska's chapter functionality.
This formmat consists of pairs of lines that start with 'CHAPTERxx=' and 'CHAPTERxxNAME=' respectively. The first one contains the start timestamp while the second one contains the title. Here's an example:
CHAPTER01=00:00:00.000 CHAPTER01NAME=Intro CHAPTER02=00:02:30.000 CHAPTER02NAME=Baby prepares to rock CHAPTER03=00:02:42.300 CHAPTER03NAME=Baby rocks the house
mkvmerge(1) will transform every pair or lines into one Matroska ChapterAtom. It does not set any ChapterTrackNumber which means that the chapters all apply to all tracks in the file.
As this is a text file character set conversion may need to be done. See the section about text files and character sets for an explanation how mkvmerge(1) converts between character sets.
The XML based chapter format looks like this example:
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE Chapters SYSTEM "matroskachapters.dtd"> <Chapters>
<EditionEntry>
<ChapterAtom>
<ChapterTimeStart>00:00:30.000</ChapterTimeStart>
<ChapterTimeEnd>00:01:20.000</ChapterTimeEnd>
<ChapterDisplay>
<ChapterString>A short chapter</ChapterString>
<ChapterLanguage>eng</ChapterLanguage>
</ChapterDisplay>
<ChapterAtom>
<ChapterTimeStart>00:00:46.000</ChapterTimeStart>
<ChapterTimeEnd>00:01:10.000</ChapterTimeEnd>
<ChapterDisplay>
<ChapterString>A part of that short chapter</ChapterString>
<ChapterLanguage>eng</ChapterLanguage>
</ChapterDisplay>
</ChapterAtom>
</ChapterAtom>
</EditionEntry> </Chapters>
With this format three things are possible that are not possible with the simple chapter format:
The mkvtoolnix distribution contains some sample files in the doc subdirectory which can be used as a basis.
The following lists the supported XML tags, their data types and, where appropriate, the valid range for their values:
Chapters (master)
EditionEntry (master)
EditionUID (unsigned integer, valid range: 1 <= value)
EditionFlagHidden (unsigned integer, valid range: 0 <= value <= 1)
EditionFlagDefault (unsigned integer, valid range: 0 <= value <= 1)
EditionFlagOrdered (unsigned integer, valid range: 0 <= value <= 1)
ChapterAtom (master)
ChapterAtom (master)
ChapterUID (unsigned integer, valid range: 1 <= value)
ChapterTimeStart (unsigned integer)
ChapterTimeEnd (unsigned integer)
ChapterFlagHidden (unsigned integer, valid range: 0 <= value <= 1)
ChapterFlagEnabled (unsigned integer, valid range: 0 <= value <= 1)
ChapterSegmentUID (binary, valid range: 1 <= length in bytes)
ChapterSegmentEditionUID (unsigned integer, valid range: 1 <= value)
ChapterPhysicalEquiv (unsigned integer)
ChapterTrack (master)
ChapterTrackNumber (unsigned integer, valid range: 1 <= value)
ChapterDisplay (master)
ChapterString (UTF-8 string)
ChapterLanguage (UTF-8 string)
ChapterCountry (UTF-8 string)
ChapterProcess (master)
ChapterProcessCodecID (unsigned integer)
ChapterProcessPrivate (binary)
ChapterProcessCommand (master)
ChapterProcessTime (unsigned integer)
ChapterProcessData (binary)
When splitting files mkvmerge(1) will correctly adjust the chapters as well. This means that each file only includes the chapter entries that apply to it, and that the timestamps will be offset to match the new timestamps of each output file.
mkvmerge(1) is able to copy chapters from Matroska source files unless this is explicitly disabled with the --no-chapters option. The chapters from all sources (Matroska files, Ogg files, MP4 files, chapter text files) are usually not merged but end up in separate ChapterEditions. Only if chapters are read from several Matroska or XML files that share the same edition UIDs will chapters be merged into a single ChapterEdition. If such a merge is desired in other situations as well then the user has to extract the chapters from all sources with mkvextract(1) first, merge the XML files manually and mux them afterwards.
Matroska's tag system is similar to that of other containers: a set of KEY=VALUE pairs. However, in Matroska these tags can also be nested, and both the KEY and the VALUE are elements of their own. The example file example-tags-2.xml shows how to use this system.
Matroska tags do not automatically apply to the complete file. They can, but they also may apply to different parts of the file: to one or more tracks, to one or more chapters, or even to a combination of both. The the Matroska specification[5] gives more details about this fact.
One important fact is that tags are linked to tracks or chapters with the Targets Matroska tag element, and that the UIDs used for this linking are not the track IDs mkvmerge(1) uses everywhere. Instead the numbers used are the UIDs which mkvmerge(1) calculates automatically (if the track is taken from a file format other than Matroska) or which are copied from the source file if the track's source file is a Matroska file. Therefore it is difficult to know which UIDs to use in the tag file before the file is handed over to mkvmerge(1).
mkvmerge(1) knows two options with which you can add tags to Matroska files: The --global-tags and the --tags options. The difference is that the former option, --global-tags, will make the tags apply to the complete file by removing any of those Targets elements mentioned above. The latter option, --tags, automatically inserts the UID that mkvmerge(1) generates for the tag specified with the TID part of the --tags option.
Let's say that you want to add tags to a video track read from an AVI. mkvmerge --identify file.avi tells you that the video track's ID (do not mix this ID with the UID!) is 0. So you create your tag file, leave out all Targets elements and call mkvmerge(1):
$ mkvmerge -o file.mkv --tags 0:tags.xml file.avi
mkvmerge(1) supports a XML based tag file format. The format is very closely modeled after the Matroska specification[5]. Both the binary and the source distributions of MKVToolNix come with a sample file called example-tags-2.xml which simply lists all known tags and which can be used as a basis for real life tag files.
The basics are:
The new Matroska tagging system only knows two data types, a UTF-8 string and a binary type. The first is used for the tag's name and the <String> element while the binary type is used for the <Binary> element.
As binary data itself would not fit into a XML file mkvmerge(1) supports two other methods of storing binary data. If the contents of a XML tag starts with '@' then the following text is treated as a file name. The corresponding file's content is copied into the Matroska element.
Otherwise the data is expected to be Base64 encoded. This is an encoding that transforms binary data into a limited set of ASCII characters and is used e.g. in email programs. mkvextract(1) will output Base64 encoded data for binary elements.
The deprecated tagging system knows some more data types which can be found in the official Matroska tag specs. As mkvmerge(1) does not support this system anymore these types aren't described here.
The following lists the supported XML tags, their data types and, where appropriate, the valid range for their values:
Tags (master)
Tag (master)
Targets (master)
TargetTypeValue (unsigned integer)
TargetType (UTF-8 string)
TrackUID (unsigned integer)
EditionUID (unsigned integer)
ChapterUID (unsigned integer)
AttachmentUID (unsigned integer)
Simple (master)
Simple (master)
Name (UTF-8 string)
TagLanguage (UTF-8 string)
DefaultLanguage (unsigned integer)
String (UTF-8 string)
Binary (binary)
With a segment info XML file it is possible to set certain values in the "segment information" header field of a Matroska file. All of these values cannot be set via other command line options.
Other "segment information" header fields can be set via command line options but not via the XML file. This includes e.g. the --title and the --timestamp-scale options.
There are other elements that can be set neither via command line options nor via the XML files. These include the following elements: DateUTC (also known as the "muxing date"), MuxingApp, WritingApp and Duration. They're always set by mkvmerge(1) itself.
The following lists the supported XML tags, their data types and, where appropriate, the valid range for their values:
Info (master)
SegmentUID (binary, valid range: length in bytes == 16)
SegmentFilename (UTF-8 string)
PreviousSegmentUID (binary, valid range: length in bytes == 16)
PreviousSegmentFilename (UTF-8 string)
NextSegmentUID (binary, valid range: length in bytes == 16)
NextSegmentFilename (UTF-8 string)
SegmentFamily (binary, valid range: length in bytes == 16)
ChapterTranslate (master)
ChapterTranslateEditionUID (unsigned integer)
ChapterTranslateCodec (unsigned integer)
ChapterTranslateID (binary)
The Matroska file layout is quite flexible. mkvmerge(1) will render a file in a predefined way. The resulting file looks like this:
[EBML head] [segment {meta seek #1} [segment information] [track information] {attachments} {chapters} [cluster 1] {cluster 2} ... {cluster n} {cues} {meta seek #2} {tags}]
The elements in curly braces are optional and depend on the contents and options used. A couple of notes:
The shortest possible Matroska file would look like this:
[EBML head] [segment [segment information] [track information] [cluster 1]]
This might be the case for audio-only files.
mkvmerge(1) allows the user to chose the timestamps for a specific track himself. This can be used in order to create files with variable frame rate video or include gaps in audio. A frame in this case is the unit that mkvmerge(1) creates separately per Matroska block. For video this is exactly one frame, for audio this is one packet of the specific audio type. E.g. for AC-3 this would be a packet containing 1536 samples.
Timestamp files that are used when tracks are appended to each other must only be specified for the first part in a chain of tracks. For example if you append two files, v1.avi and v2.avi, and want to use timestamps then your command line must look something like this:
$ mkvmerge ... --timestamps 0:my_timestamps.txt v1.avi +v2.avi
There are four formats that are recognized by mkvmerge(1). The first line always contains the version number. Empty lines, lines containing only whitespace and lines beginning with '#' are ignored.
This format starts with the version line. The second line declares the default number of frames per second. All following lines contain three numbers separated by commas: the start frame (0 is the first frame), the end frame and the number of frames in this range. The FPS is a floating point number with the dot '.' as the decimal point. The ranges can contain gaps for which the default FPS is used. An example:
# timestamp format v1 assume 27.930 800,1000,25 1500,1700,30
In this format each line contains a timestamp for the corresponding frame. This timestamp must be given in millisecond precision. It can be a floating point number, but it doesn't have to be. You have to give at least as many timestamp lines as there are frames in the track. The timestamps in this file must be sorted. Example for 25fps:
# timestamp format v2 0 40 80
In this format each line contains a duration in seconds followed by an optional number of frames per second. Both can be floating point numbers. If the number of frames per second is not present the default one is used. For audio you should let the codec calculate the frame timestamps itself. For that you should be using 0.0 as the number of frames per second. You can also create gaps in the stream by using the 'gap' keyword followed by the duration of the gap. Example for an audio file:
# timestamp format v3 assume 0.0 25.325 7.530,38.236 gap, 10.050 2.000,38.236
This format is identical to the v2 format. The only difference is that the timestamps do not have to be sorted. This format should almost never be used.
mkvmerge(1) exits with one of three exit codes:
mkvmerge(1) uses the default variables that determine the system's locale (e.g. LANG and the LC_* family). Additional variables:
MKVMERGE_DEBUG, MKVTOOLNIX_DEBUG and its short form MTX_DEBUG
MKVMERGE_ENGAGE, MKVTOOLNIX_ENGAGE and its short form MTX_ENGAGE
mkvinfo(1), mkvextract(1), mkvpropedit(1), mkvtoolnix-gui(1)
The latest version can always be found at the MKVToolNix homepage[6].
Moritz Bunkus <moritz@bunkus.org>
| 2019-02-09 | MKVToolNix 31.0.0 |